Add Rust SDK to sdk-options.md

[AlexanderProd]

I've written a small SDK for using email and sms with azure communication services in Rust.

[prmerger-automator[bot]]

@AlexanderProd : Thanks for your contribution! The author(s) have been notified to review your proposed change.

[learn-build-service-prod[bot]]

Learn Build status updates of commit d779e86:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
articles/communication-services/concepts/sdk-options.md	:white_check_mark:Succeeded

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[Court72]

@sloanster

Can you review the proposed changes?

Important: When the changes are ready for publication, adding a #sign-off comment is the best way to signal that the PR is ready for the review team to merge.

#label:"aq-pr-triaged" @MicrosoftDocs/public-repo-pr-review-team

[AlexanderProd]

Any update here? :)

[PMEds28]

@sloanster

Can you review this old PR and determine whether it needs to be closed or merged?

@MicrosoftDocs/public-repo-pr-review-team

[ttorble]

I sent email to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team

[v-dirichards]

@sloanster Can you review this old PR and determine whether it needs to be closed or merged?

IMPORTANT: When the changes are ready for publication, add a #sign-off comment to signal that the PR is ready for the review team to merge. If the changes no longer apply, add an explanation and a #please-close comment to close the PR.

@MicrosoftDocs/public-repo-pr-review-team

[v-dirichards]

I sent a Teams message to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team